Materials

Target cells (any adherent or suspension cell line that can express proteins from transfected DNAs may be used)

Culture medium (the presence of serum does not inhibit the SNAP‐tag reaction)

Plasmid encoding SNAP‐tag fusion protein: the original SNAP‐tag, SNAP26m, has been replaced by a faster labeling variant,
SNAPf (available from NEB) that allows for reduction of substrate concentration and incubation times

Transfection reagent (Fugene, Roche; Lipofectamine, Invitrogen); an electroporation system (Amaxa) may also be used

Infrared fluorescence scanner (Odyssey, LI‐COR Biosciences, http://www.licor.com/): in this protocol, detection of IRDye 800CW is with an Odyssey infrared scanner; depending on the fluorophore used, gels
can be scanned using a number of commercially available imagers (e.g., Typhoon from GE Healthcare or Pharos FX from BioRad)
using appropriate lasers and filter sets